SCICEX Hydrographic Data, 1997 and 1998

The Scientific Ice Expeditions (SCICEX) Program was a series of five multidisciplinary scientific cruises that utilized US Navy operational submarines as platforms for sampling the Arctic Ocean. The program's numerous principal investigators worked towards the overarching goal of characterizing the upper layers of the Arctic Ocean as completely as possible. This data set includes hydrographic data obtained during the 1997 and 1998 (third and fourth) SCICEX cruises, aboard the USS Archerfish and the USS Hawkbill, respectively. Water column profile data were collected using a submarine-launched conductivity, temperature, and depth (CTD) probe. Probe depths were computed based on a known fall rate, temperature (T) and conductivity values were measured by probe sensors, and salinity was computed from these values. Derived variables, including pressure (calculated from depth and latitude), potential temperature, sigma-t (a representation of density), and sigma-theta (sigma-t calculated with potential temperature), are also included. Profile data were generally collected to a depth of 1000 m at 1-m depth intervals, with variable horizontal distance between the profiles. Data were collected between September 3 and October 2, 1997, and between August 1 and September 2, 1998, along extensive transects within the Arctic Ocean.

科学冰考察（Scientific Ice Expeditions, SCICEX）计划是一系列共5个多学科科学航次，以美国海军现役作战潜艇作为北冰洋采样作业平台。该计划的多位首席研究员共同致力于总体目标：尽可能全面地刻画北冰洋上层水体的特征。本数据集涵盖1997年与1998年（即该计划第三、第四航次）SCICEX航次采集的水文数据，分别由" Archerfish号潜艇（USS Archerfish）"与" Hawkbill号潜艇（USS Hawkbill）"执行作业。水柱剖面数据通过潜艇搭载的电导率-温度-深度（Conductivity, Temperature, Depth, CTD）探头采集：探头水深基于已知的下沉速率计算得出，探头传感器直接测量温度（T）与电导率数值，并通过二者计算盐度。数据集同时包含衍生变量，包括由水深与纬度计算得到的压力、位温、sigma-t（密度表征参数）以及基于位温计算得到的sigma-theta（即基于位温计算的sigma-t）。剖面数据通常以1米深度间隔采集至1000米水深，各剖面间的水平间距存在差异。数据采集时段分别为1997年9月3日至10月2日，以及1998年8月1日至9月2日，采集区域覆盖北冰洋内多条大范围考察断面。